Should 14 year old pay Zakat on benefit money that is being saved?

My little brother is diabetic and gets benefit money from the government every year that my parents have held for him until he is 18. This money is being saved with the intention it may go towards improving his quality of life should something in future help with his diabetes. We need to know if we should be paying Zakat on this money every year? He is 14 years old and the money is held on his own bank account that my parents transfer to it.